1. Field of the Invention
This invention relates to multicontact electrical connectors, particularly to electrical connectors for establishing an insulation displation contact with conductors, such as wires, and interconnecting the conductors to a plurality of contact elements such as pins located in one or more rows in a pin grid array.
2. Description of the Prior Art
U.S. Pat. No. 4,159,158 discloses a multicontact electrical connector using insulation displation or displacement terminals to interconnect individual wires or conductors to terminal posts on 0.100 inch centers on a printed circuit or panel board. That connector employs a plurality of individual terminals each having an insulation displacement contact section in which a wire is inserted into the contact terminal. The connector housing in which the contact terminal is positioned supports the contact terminal axially as a conductor is inserted into the insulation displacement contact section as well as supporting the insulation displation contact surface laterally. One of the principal advantages of the electrical connector disclosed in U.S. Pat. No. 4,159,158 is that conductors, such as insulated wires, can be mass terminated to a plurality of terminals in a single operation. This mass termination technique greatly simplifies interconnection of the conductors to the terminals and yields a corresponding saving in assembly costs. Although that connector does provide a low cost interconnection system suitable for use in large numbers in the electronics industry, there is an ever increasing need to reduce both the material costs and the assembly costs for interconnection systems between individual insulated conductors and contact elements such as terminal posts located on closely spaced centerlines.
The corresponding need to reduce material costs, to reduce assembly costs, and to maintain closely spaced centerlines between terminals in the multicontact connector are generally contradictory. For example, the connector depicted in U.S. Pat. No. 4,062,610 can be used to mass terminate conductors in a housing on closely spaced centerlines. However, the fabrication of the contact terminal, its plating, and the amount of material needed in the fabrication of the terminal can be relatively expensive. Similarly, the connector disclosed in U.S. Pat. No. 4,385,794, while exhibiting a number of advantages which have made this connector a highly successful interconnection system, does employ a large amount of material to fabricate the connector terminal.
Contacts of the type shown in U.S. Pat. No. 4,385,794, and of the type involved in the instant invention are arranged in dense arrays of closely spaced terminals typically having centerline spacings of 0.100 inches between adjacent terminals. The wire used on this type spacing is typically 22-28 guage with the diameter of the insulation approximately 0.050 inches. Therefore, the formed width of the contacts must, per se, be greater than 0.050 inches but less than 0.100 inches. Contacts of this size are typically left on the carrier strip after being stamped and formed as the contacts are easier to handle while connected to the carrier strip. Once all contacts are inserted into the respective cavities, the carrier strip may be cut off leaving all contacts in place within the connector. In order to simplify the manufacturing and assembling costs involved, it is preferable to have a contact which, in the flat blank stage, is also less than the centerline spacing of the connector cavities, in this case, less than 0.100 inches. If this design is achieved, all of the contacts can be loaded within the housing cavities from a single carrier strip. If the width of the contact, in the flat blank stage, is greater than the centerline spacing of the connector cavities, the contacts could not be loaded into the connector cavities from a single carrier strip, because the centerline spacings of the formed contacts could not possibly be on the centerline spacing of the connector cavities.
Referring again to the contact disclosed in U.S. Pat. No. 4,385,794, and more specifically to his FIG. 1, it is apparent from the box type receptacle portion 16, that the unfolded width of the flat stamping is wider than the centerline spacing of the contacts. Therefore, the installation of the contacts is made more difficult as more than one carrier strip is required to load all contacts within the housing. Although a connector of the type shown in U.S. Pat. No. 4,435,035 can be employed with a mass termination technique in which conductors are inserted into the insulation displacement terminals while the terminals are fully inserted into the housing, centerline spacing for which this operation can be accomplished may be limited, and this connector does employ a large amount of material to form the terminal.
A connector having an insulation displacement slot formed by stamped metal forming two upstanding plates interconnected by a bight portion is shown in U.S. Pat. No. 4,335,929. Although this connector does allow close centerline spacing between adjacent terminals in the same connector, the terminals U-portion in U.S. Pat. No. 4,335,929 is relatively high as the wire terminating slot must be long enough to accommodate a conductor and allow good electrical connection, and a terminal of this height does not allow lateral stacking with adjacent connectors and maintain 0.100 inches lateral spacing between centers.
A terminal is disclosed in U.S. Pat. No. 4,527,857 which utilizes an insulation displacement slot at one end and folded arms at the opposite end to contact blade type terminals. However, this contact could not be used to contact posts on a square matrix.
As shown in FIG. 1, the contact has two pairs of parallel and opposed contacts for contacting a blade terminal. As blade terminals are longer than 0.100 inches, the terminals shown in U.S. Pat. No. 4,527,857 could not be utilized for a 0.100 square matrix.
The connector disclosed herein not only achieves the excellent performance exhibited by these former interconnection systems but also offers even lower cost interconnection system by significantly reducing the amount of material which must be used to fabricate the contact terminal, by facilitating plating on only a single surface of the stamped terminal blank, and by providing an insulating housing which can be positioned side by side and end to end with similar contact housing assemblies to form an interconnection system between contact elements, such as terminal posts located on closely spaced centers in a multidimensional array.